How Sportsbooks Set Betting Lines

The odds and betting lines that sportsbooks post for bets are obviously and understandably the obsession of sports bettors. They are a big part of whether you win or lose as a bettor. Too many gamblers don’t know exactly where those lines come from. Bettors that understand the process of how lines and odds are set have a better shot at being successful. 

Key Points

– Sportsbooks set betting lines in a number of different ways.

– The job of oddsmakers is not to correctly predict the outcome of a game.

Setting Betting Lines Overview

Although this is oversimplified, there are basically three ways that sportsbooks generate the lines that they post. The first and most popular option is for them to seek guidance from a service.

Many sportsbooks use Las Vegas Sports Consultants. As early as possible, LVSC and other organizations set game lines using computer power ratings as a starting point. They make adjustments as necessary. 

Once the books have those lines, they may change them slightly on their own. They usually don’t deviate too much because if they do and other books don’t, they will experience an unexpected surge in action.

Sportsbooks also set the odds on their own. This happens more frequently in sports where there is a tight time frame and quick decisions are required. It also happens when odds are being set for obscure events or novel prop bets are being offered.

Finally, some books simply follow the market leaders by establishing their lines based on what other sportsbooks do and then factoring in how the early bettors react. These are typically sportsbooks that don’t draw in the early bettors.


Sportsbooks Are Not Aiming to Be Accurate

The aim of the bookmakers is not to be accurate. They are not predicting the actual outcome or actual point spread of a game. 

Many novice bettors believe that sportsbooks are attempting to predict the game’s outcome when they offer betting lines. Though they frequently prove to be quite accurate, it’s not their goal.

The bookmakers’ actual objective is to choose a line that allows them to collect an even amount of action on both teams. This is how the books make money.

Sportsbooks are guaranteed to break even if they have the same amount of money wagered on both sides of the bet. It’s important to understand that we’re not referring to having an equal number of bettors on each side here. Rather, we are talking about an equal amount of money.

Balancing the Action

Before accepting bets on a game, the books frequently already know they won’t be able to balance the action. Therefore, it is their responsibility to establish the line and tweak it as necessary to achieve a level of risk they can handle. 

To achieve this, the books must make educated assumptions about two things. One is the likely betting patterns of the general public. The other is how sharp bettors, the pros, will bet.

The worst-case scenario is that the sportsbooks draw a line where the public and smart money are evenly split on a particular side. The vast majority of the financial resources will then be on one side. Accordingly, if the other side of the spread covers, the books could make a sizable profit. However, if the public covers, they would lose money. 

In a situation like that, books are essentially gambling, and they detest gambling. Finding the point where the general public and the smart money are likely to hold different opinions is the main objective of setting a line, so to speak. 

In order to increase their margin for error, books frequently add one or two points to the side where they believe the public will lean. Smart money isn’t always easy to identify. However, once the lines have been established, they can quickly determine whether they are correct or not and adjust the line accordingly. 

Timing & Betting Lines

A sporting events’ timing has an impact on betting lines, point spreads, etc.. For instance, the length of time between games in various sports greatly affects how lines are set. 

In the NFL, lines are set late on Sunday night, shortly after the previous week’s games are over. They have a full week to be examined, adjusted as necessary, and bet up or down. 

Sportsbooks can never afford to make major errors, but because of the length of the football season and the fact that most bets are placed closer to kickoff, the books have time to adjust a point spread if it isn’t initially accurate. 

The line is typically set the night before a game for basketball, baseball, and hockey. Most sportsbooks don’t release their line until the morning of the game. Because of the shorter time frame, there is less opportunity for the books to respond and adjust. That means mistakes are more accessible to bettors than they are in football. 

A savvy amateur bettor has a better chance of finding an opportunity to get real value the closer the window of time between the posting of the lines and the start of the game is. The bookmakers only really have one chance to get things right. On busy days, they have to get several lines right at once. When you factor in things like halftime bets, bettors should see that there are plenty of opportunities to capitalize on betting lines.